1. Field of the Invention
The present invention relates to compositions of the core-sheath type. More particularly, the present invention relates to cosmetic compositions having two or more components that are segmented therein. In addition, the present invention relates to the method of and apparatus for making such compositions.
2. Description of the Prior Art
Many consumers favor wax-free cosmetics. Wax-free cosmetics do not have a waxy feel or create a wax-like build-up. An example of a substantially wax-free cosmetic composition is provided in U.S. Pat. No. 5,882,662, issued on Mar. 16, 1999 to Pahlck et al., titled Cosmetic Compositions Containing Smectite Gels. This patent provides for a cosmetic composition comprising a smectite clay and a lipophilic polar solvent, which gels without the addition of a polar activator and without high shear.
However, many wax-free cosmetics lack the advantages inherent to wax-based cosmetics, which are preferred by many other consumers. Namely, wax-based cosmetics have high shine, soft feel, and good spreadability. Conventional wax-based lipsticks are manufactured by adding fats, oils, pigments or lakes, and other non-aqueous ingredients to a natural or synthetic hard wax base that is melted to enable the ingredients to be thoroughly mixed. Then, the mixed ingredients are cast into a mold that, after cooling, provides a cosmetic product, such as a lipstick.
Consumers would favor a cosmetic composition that could be molded to contain both the wax-based benefits of high shine, soft feel, and good spreadability, and the non-wax based benefits of no waxy feel and no wax-like build-up. However, the formation of such a cosmetic composition is problematic.
U.S. Pat. No. 4,291,018, which issued on Sep. 22, 1981 to Oeda et al., provides a lipstick of the core-sheath type having a first composition of low-viscosity, oily ingredients and a second composition of viscous, oily ingredients. This patent also discloses that, if the difference in melt (i.e. liquefying) temperatures between the two compositions is greater than 5° C., the desirable properties of each composition fails to be fully achieved.
Given the foregoing, a need exists for a segmented cosmetic composition that can combine the advantages and benefits of both wax-free and wax-based compositions. There is also a need for an efficient method of and apparatus for manufacturing such a cosmetic composition.